Biology Entrance test questions

1. Pyruvic acid is formed during:
(a) ornithine cycle. (b) Krebs cycle
(c) glycolysis (d) photosynthesis
2. .Which of the following are essential for formation of ATP ?
(a) Fe and Mo (b) N and P
(c) Fe and P (d) Mg and Mn
3. Why carbohydrates are more efficient inproviding energy than fats and proteins?
(a) Carbohydrates have high molecular weight
(b) They have less oxygen content than fats, therefore, require less molecular oxygen
(c) Fats have less molecular weight
(d) They have more oxygen content and therefore require less mo- lecular oxygen to provide energy.
. Which one of the following can respire in anaerobic conditions? (a) leaves (b) stem (c) roots (d) seeds
5. The value (II R.Q. of a succulent plant at night is :
(a) one (h) more than one (c) infinity (d) zero
o. Last product of food oxidation is :
(a) pyre vita acid (b) citric acid (c) CO2 + H2O (d) oxygen
6. Photorespiration is favoured by :
(a) low light and high 02 (b) low 02 and high CO2
(c) low temperature and high 02 (d) high 02 and low CO2
7. Compensation point is :
(a) when there is enough water just to meet the requirements of plant.
(b) when rate of photosynthesis is equal to the rate of respiration.
(c) when there is neither photosynthesis nor respiration.
(d) when the entire food synthesized in photosynthesis remains unutilized.
9. Ascent of sap takes place through:
(a) Phloem (b) Cambium
(c) Xylem or xylem vessel element (d) Epidermis
10. Which of the following is a rapid type of absorption?,
(a) Root absorption (b) Active absorption
(c) Salt absorption (d) Passive absorption
11 • Root cap has no role in water absorption because:
(a) It has loosely arranged cells
(b) It has no cells containing chloroplasts
(c) It has no root hairs
(d) It has no direct connection with vascular system
12. The ultimate cause for the movement of water against gravity in a tree is
(a) Imbibiton (b) Photosynthesis
(c) Transpiration (d) Osmosis
. The principal pathways by which water is translocated in angiosperm is
01) Xylem vessel system (b), Xylem and phloem together
(c) Sieve tube members of phloem (d) Sie-ife cells of phloem
14. Transpiration - Cohesion tension theory operates in

(a) Passive absorption (b) Active absorption
(c) Both active and passive (d) None of these
15. Root pressure in a plant is measured by
(a) Barometer (b) Thermometer (c) Photometer
16. Water available to plants is:
(a) Hygroscopic water (b) Crystalline water
(c) Gravitational water (d) Capillary water
17. Water enters into root hairs mainly due to: (a) Atmospheric pressure
(c) Turgor pressure
18. Root pressure is due to:
(a) passive absorption (b) active absorption
(c) increase in transpiration (d) increase in photosynthesis
19. Root pressure can be demonstrated by means of
(a) transpiration (b) guttation (c) wilting (d) exudation
20. The main difference between active and passive dansport across cell membrane is that
(a) active transport occurs more rapidly than pagsive transport
(b) passive transport is non-selective
(c) passive transport requires a concentration gradient across the cell membrane whereas active transport requires metabolic energy
(d) passive transport is confined to anions and active transport is for cations only
21. The most accepted theory for the ascent of sap in plants was put forward by
(a) J.C. Bose (b) Mune (c) Stra.sburger (d) Dixon and Jolly
22. Guttation occurs through:
(a) Hydathodes (b) Stomata (c) Root hairs (d) Flower buds
23. The force of tension - cohesion exceeds root pressure on a:
(a) Foggy morning (b) Rainy day
(c) Sunny day (d) Full moon light
24. Which one of the following is responsible to make water rise inplants,
100 feet tall:
(a) Air pressure (b) Capillary action
(c) Root pressure (d) Passive absorption
25. Imbibition theory of Sachs as explanation for ascent of sap, is wrong
because:
(a) water moves through lumen and not along the walls
(b) It involves expenditure of energy
(c) Sap rises along the walls of living cells.
(d) Cellulose walls of xylem do not show imbibition
26. In active absorption of water:
(a) energy is not used
(b) the photosynthesis provides energy
(c) the root respiration gives energy
(d) the transpiration pull provides force for absorbing water
27. Water is absorbed when outside solution is :
(a) Isotonic (b) Hypotonic
(c) Hypertonic (d) None of these
28. A man applied fertilizers heavily on his lawns then he gave more water. A few days later the grass turned brown because
(a) transpiration rate increased due to excessive water
(b) the roots were killed due to loss of water by osmosis
(c) heavy fertilizers affected photosynthesis
(d) excessive water fertilizer caused diffusion of water in sub soil
water
29. During absorption of water by roots the water potential of cell sap
is lower than that of :
(a) pure water and soil solution
(b) neither pure water nor soil solution
(c)pure water but higher than that of soil solution
(d) soil solution but higher than that of pure water
30. In water logged soil, plants can not grow properly because the soil is
(a) physiologically wet (b) physiologically dry
(d) None of the above